Before the first Earth Day there was an eco-documentary, 'Our Vanishing Wilderness.' Now 40 years later, environmentalists can watch it again.

While we seem to have seen a sudden surge in the number of eco-documentaries making their way onto TV and into theaters since An Inconvenient Truth, filmmakers and videographers have been documenting human effects on our environment for decades. In fact, the first environmental TV documentary series was shot back in 1970 — before the first Earth Day!

Based on a 1969 book by the same name, Our Vanishing Wilderness shows the pollution and environmental issues were already raising concerns 40 years ago. Shot by nature photographer Shelly Grossman and written by Mary Louise Grossman, each episode focuses on a specific ecosystem that’s being compromised or threatened due to human activity — like how Santa Barbara’s marine life is affected by pesticide runoff and an oil spill, or what the potential effects of the Alaska Pipeline would be on animals living around the project.

Watch Our Vanishing Wilderness to see what eco-concerns were on the minds of environmentalists 40 years ago — and how this first environmental TV series in the U.S. compares to the green documentaries we see today.